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Acute myeloid leukemia (AML) is associated with poor outcome mainly because of relapse. The best antileukemic treatment is allogeneic stem cell transplantation. However, the associated significant nonrelapse mortality limits both the application and outcome of the procedure. Recent advances in understanding the genetic landscape of the disease enable educated selection of patients. Improved treatment protocols, supportive therapy, patient selection, and posttransplant manipulations all contribute to a better outcome., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Purpose of Review: Induction followed by postremission therapy is recognized as the main road toward cure in acute myeloid leukemia (AML). Induction approach has not changed substantially for many years. Despite identifying numerous heterogeneous factors in AML, bench-derived insights are sluggishly translated into clinical protocols. In the current review, advances in intensified dose induction protocols, risk stratification, and disease monitoring are presented. Some promising as well as disappointing agents used for tailoring and targeting therapies in AML are also discussed., Recent Findings: Intensifying anthracycline dose in young AML patients was recently shown to improve induction results. Importantly, maximal doses in induction have been shown to be safe also in older adults, negating a common perception that too often led to attenuation of induction therapy in this population. Novel targeted agents and the explosive number of newly identified prognostic factors or disease-specific biomarkers are promoting AML therapy toward a more personalized future., Summary: Survival of AML patients is constantly improving. High doses of 'old drugs' for chemotherapy induction, followed by a postremission combination of chemotherapy and novel targeted agents may hold the key for cure. Disease-specific molecular abnormalities may play a role in monitoring and guiding therapy.

We compared the outcomes of unrelated donor (URD, n = 358) with human leukocyte antigen (HLA)-matched sibling donor (MSD, n = 226) transplantations in patients with acute myeloid leukemia (AML) in first complete remission (CR1) having unfavorable cytogenetics at diagnosis. Unfavorable cytogenetic abnormalities were: complex (≥ 3 abnormalities), 32%; and noncomplex involving chromosome 7, 25%; chromosome 5, 9%; 11q or MLL rearrangements, 18%; t(6;9), 5%; and other noncomplex, 10%. URDs were HLA-well-matched (n = 254; 71%) or partially-matched (n = 104; 29%). Three-year leukemia-free survival (LFS) for MSD was 42% (95% confidence interval [CI], 35%-48%) compared with 34% (95% CI, 28%-41%) for HLA-well-matched URD and 29% (95% CI, 20%-39%) for partially-matched URD (P = .08). In multivariate analysis, HLA-well-matched URD and MSD yielded similar LFS (relative risk [RR] = 1.1, 95% CI, 0.86-1.40, P = .44) and overall survival (OS; RR = 1.06, 95% CI, 0.83-1.37, P = .63). LFS and OS were significantly inferior for HLA-partially-matched URD recipients, those with prior myelodysplastic syndrome, and those older than 50 years. All cytogenetic cohorts had similar outcomes. Patients with chronic graft-versus-host disease had a significantly lower risk of relapse (RR = 0.68, 95% CI, 0.47-0.99, P = .05). Hematopoietic cell transplantation (HCT) using HLA-well-matched URD and MSD resulted in similar LFS and OS in AML patients in CR1 with unfavorable cytogenetics. Outcomes of HCT from HLA-partially- matched URD were inferior.

Approximately 300,000 patients in the world are diagnosed annually with acute myeloid leukemia (AML). The median age at presentation has been steadily increasing over the past few decades and now is approaching 70 years. Although considerable progress has been made over the past 3 decades in the therapy of AML, two thirds of young adults still die of their disease. The therapy of AML, unlike acute lymphoblastic leukemia (ALL), is based on maximally tolerated induction and post-remission therapy, all given within a few months from diagnosis. While complete remission can be achieved in the majority of young patients, ultimate cure of the disease depends on disease eradication through the administration of post-remission therapy. This is most often done with intensive chemotherapy. Harnessing the immunologic effect of graft-versus-leukemia, as in allogeneic transplantation, has further improved the outcome for many patients. Treatment of older adults, representing the majority of patients with AML, remains quite unsatisfactory. While 40% to 50% can achieve a complete remission, less than 10% are long-term survivors, and the cure rate of older patients has only minimally improved over the past three decades. Significant progress in the treatment of this age group is urgently required. New and targeted agents have much promise, but a definitive clinical role for these has yet to be conclusively established.

We compared the treatment-related mortality, relapse rate, disease-free survival (DFS), and overall survival (OS) by cytogenetic risk group of 261 patients with acute myeloid leukemia in first complete remission (CR1) and 299 patients in CR2 in undergoing matched unrelated donor hematopoietic stem cell transplantation (HSCT). For patients in first CR, the DFS and OS at 5 years were similar for the favorable, intermediate, and unfavorable risk groups at 29% (95% confidence interval [CI], 8%-56%) and 30% (22%-38%); 27% (19%-39%) and 29% (8%-56%); and 30% (95% CI, 22%-38%) and 30% (95% CI, 20%-41%), respectively. For patients in second CR, the DFS and OS at 5 years were 42% (95% CI, 33%-52%) and 35% (95% CI, 28%-43%); 38% (95% CI, 23%-54%) and 45% (95% CI, 35%-55%); and 37% (95% CI, 30%-45%) and 36% (95% CI, 21%-53%), respectively. Cytogenetics had little influence on the overall outcome for patients in first CR. In second CR, outcome was modestly, but not significantly, better for patients with favorable cytogenetics. The graft-versus-leukemia effect appeared effective, even in patients with unfavorable cytogenetics. However, treatment-related mortality was high. Matched unrelated donor HSCT should be considered for all patients with unfavorable cytogenetics who lack a suitable HLA-matched sibling donor.

Purpose of Review: Acute myeloid leukemia is a heterogeneous disease with a prognosis determined mostly by the leukemic karyotype. Allogeneic transplant in first remission is offered to patients with intermediate- and poor-risk cytogenetics. Only the minority of patients, however, have a matched sibling donor., Recent Findings: Matched unrelated, genetically haploidentical and umbilical cord blood have been increasingly used. Pros and cons of each procedure are discussed, and whenever available, comparisons are made., Summary: With the progress made in supportive care and prophylaxis of graft-versus-host disease, significant improvement in results of transplant from alternative donors has enabled its increasing use in specific disease stages. The recommended transplant for a given patient and the timing of transplant are discussed.

Recent progress has been made in several areas in the treatment of acute myelogenous leukemia (AML): prognostic factors, allogeneic bone marrow transplantation, and new and targeted therapies. Delineation and clarification of prognostic factors have led to improved risk determination, with research moving from cytogenetics to an examination of molecular markers. Trends in the area of allogeneic bone marrow transplantation include broad adoption of reduced-intensity conditioning despite the lack of prospective comparative studies. Although the preponderance of data has established this as a feasible option, a true understanding of how much of an advantage it conveys needs to be established in prospective studies. The use of alternative donors is another advance, and recent data are promising, but survival is poor if transplantation is performed when disease is active, especially during refractory relapse or refractory disease. When haploidentical matched donors are used, survival rates appear similar to those reported with matched unrelated-donor transplants. Analysis of the data for allogeneic transplantation shows that HLA-identical sibling transplants to patients in the first complete remission (CR1) provide the highest probability of long-term survival, compared with HLA-identical sibling transplants to patients in later remissions. Similarly, unrelated-donor transplants to high-risk patients in CR1 lead to a greater degree of success than unrelated-donor transplants to patients in CR2 or later remission. Cord blood has also been established as a suitable source for hematopoietic transplantation in AML. A third area of recent progress involves new and targeted therapies. Multiple new agents with tremendous potential are in development and clinical trials. Therapy can even be tailored to several specific genetic subtypes of AML.

Allogeneic stem cell transplantation for acute myeloid leukemia (AML) using reduced-intensity conditioning (RIC) is based on the strategy of attaining donor cell engraftment with immunosuppressive agents. This approach, which relies predominantly on donor effector cells for anti-leukemic or graft-versus-leukemia effect, is being used with increased frequency. Treatment-related mortality appears less with RIC than that observed with conventional myeloablative regimens. Available data support the fact that a myeloablative regimen is not required for successful engraftment and some patients appear to be cured of their disease. Despite the plethora of clinical reports, however, no prospective studies have been conducted that establish this procedure as the preferred option in AML. On the other hand, patients formerly excluded from a myeloablative procedure such as the 'elderly' and those with significant comorbid conditions, often may be RIC transplant candidates. By using prospective controlled clinical trials, we will determine whether these encouraging RIC data are applicable to a nonselect population of AML. The transplant community now is poised to design and complete investigations to ascertain the true role of RIC in the treatment of AML.

Randomized trials of substituting high-dose cytarabine (HiDAC) for standard dose cytarabine (SDAC) during induction therapy for newly diagnosed AML have not demonstrated an improvement in the complete remission (CR) rate. Phase II trials of the scheduled administration of HiDAC after SDAC suggest an improved outcome. The hematological complications of intensification are considerable. GM-CSF after chemotherapy improved the survival of older patients in a randomized trial. Recombinant human interleukin 11, a thrombopoietic cytokine, reduced the incidence of chemotherapy-induced thrombocytopenia in patients with solid tumors. Therefore, 34 patients were treated, with newly diagnosed AML less than 56 years of age, with daunorubicin 45 mg/m2 on days 1-3, cytarabine 100mg/m2 days 1-7 and cytarabine 2g/m2 for 12 h on days 8-10 (7+3+3). rhIL-11 (50 microg/kg/day,) and GM-CSF (250 microg/kg/day) were administered subcutaneously from day 11 until recovery. The complete remission rate was 59% (90% C.I. 43-73%). The median time to recovery of neutrophils to >500 and platelets to > or =20,000 microl(-1) was 27 days (95% C.I. 27-30 days) and 25 days (95% C.I. 24-29 days), respectively. The trial does not confirm the high CR rate observed in phase II trials, despite optimal supportive care.

The primary objective of this phase 3 study was to determine whether postconsolidation immunotherapy with interleukin-2 (IL-2) and histamine dihydrochloride (HDC) improved the leukemia-free survival (LFS) of adult patients with acute myeloid leukemia (AML) in complete remission (CR). Three hundred twenty patients with AML (median age, 57 years; range, 18-84 years) were stratified by CR1 or subsequent CR (CR > 1) and randomly assigned to treatment with HDC/IL-2 or no treatment (control). Treatment comprised 10 21-day cycles with IL-2 (16 400 U/kg) plus HDC (0.5 mg); both compounds were administered by subcutaneous injection twice daily. Study arms were balanced for age, sex, previous treatment, leukemic karyotypes, time from CR to inclusion, and frequency of secondary leukemia. Three years after enrollment of the last patient, treatment with HDC/IL-2 was found to improve LFS over control in the study population (CR1 + CR > 1, n = 320; P < .01, log-rank test). For patients in CR1 (n = 261), treatment significantly improved LFS (P = .01) with 3-year LFS estimates of 40% (HDC/IL-2) compared with 26% (control). Side effects were typically mild to moderate. These results indicate that HDC/IL-2 treatment offers an efficacious and tolerable treatment for patients with AML in remission.

Although improvement in outcomes has occurred in younger adults with acute myeloid leukemia (AML) during the past 4 decades, progress in older adults has been much less conspicuous, if at all. Approximately 50% to 75% of adults with AML achieve complete remission (CR) with cytarabine and an anthracycline such as daunorubicin or idarubicin or the anthracenedione mitoxantrone. However, only approximately 20% to 30% of the patients enjoy long-term disease survival. Various postremission strategies have been explored to eliminate minimal residual disease. The optimal dose, schedule, and number of cycles of postremission chemotherapy for most patients are not known. A variety of prognostic factors can predict outcome and include the karyotype of the leukemic cells and the presence of transmembrane transporter proteins, which extrude certain chemotherapy agents from the cell and confer multidrug resistance and mutations in or over expressions of specific genes such as WT1, CEBPA, BAX and the ratio of BCL2 to BAX, BAALC, EVI1, KIT, and FLT3. Most recently, insights into the molecular pathogenesis of AML have led to the development of more specific targeted agents and have ushered in an exciting new era of antileukemia therapy. Such agents include the immunoconjugate gemtuzumab ozogamicin, multidrug resistance inhibitors, farnesyl transferase inhibitors, histone deacetylase and proteosome inhibitors, antiangiogenesis agents, Fms-like tyrosine kinase 3 (FLT3) inhibitors, and apoptosis inhibitors.

The incidence of the major clonal myeloid diseases, clonal cytopenias, acute, subacute (oligoblastic), and chronic myelogenous leukemia, polycythemia vera, thrombocythemia, and idiopathic myelofibrosis increases in a log-linear manner from young adulthood through advanced age. In older patients, diseases requiring cytotoxic treatment are more difficult and less successful to manage because comorbid conditions and poor performance status are more prevalent, decreasing the tolerance to therapy and increasing the frequency of side effects. This age effect is highlighted by the dramatically less favorable outcome in older than younger patients with acute myeloid leukemia with similar "favorable" cytogenetic changes. In addition, in acute and subacute myeloid leukemia in older patients, the disease is intrinsically more resistant to therapy. Overexpression of drug resistance genes and unfavorable genetic mutations are more prevalent in older patients and provide evidence that acute myeloid leukemia is often qualitatively different in these patients. The gradient of age effects is continuous; the frequency of poor outcome increasing by decade (or less). The decline in survival becomes especially steep as quinquagenarians (50-year-olds) age to nonagenarians (90-year-olds). Although improved drug schedules have led to significant improvements in event-free survival in younger patients, these improvements have been far less evident in older patients. New approaches, especially the development of drugs aimed at new targets, will be required to obtain a high frequency of long-term remissions in older patients. Agents that reverse inherent cellular drug resistance, farnesyltransferase inhibitors, BCL-2 inhibitors, and FLT3 inhibitors are early examples of such approaches.

The optimal induction for older adults with acute myeloid leukemia (AML) is unknown. Several anthracyclines have been proposed, but the data remain equivocal. Additionally, few prospective trials of priming with hematopoietic growth factors to cycle leukemia cells prior to induction chemotherapy have been conducted. Three hundred and sixty-two older adults with previously untreated AML were randomized to either daunorubicin, idarubicin or mitoxantrone with a standard dose of cytarabine as induction therapy. In addition, 245 patients were also randomized to receive granulocyte-macrophage colony-stimulating factor (GM-CSF) or placebo beginning 2 days prior to induction chemotherapy and continuing until marrow aplasia. No difference was observed in the disease-free overall survival or in toxicity among patients receiving any of the 3 induction regimens or among those receiving growth factor or placebo for priming. However, the complete remission rate for the first 113 analyzable patients, who did not participate in the priming study and started induction therapy 3 to 5 days earlier than those who did, was significantly higher (50% versus 38%; P =.03). None of the anthracyclines is associated with improved outcome in older adults. Priming with hematopoietic growth factor did not improve response when compared with placebo. Furthermore, delaying induction therapy in older adults may lead to a lower complete remission rate.

CD65s appears when the progenitor antigen CD34 disappears, suggesting that this sialylated carbohydrate antigen marks a turning point in normal myeloid differentiation. We characterized acute myeloid leukemia (AML) with low CD65s expression (CD65s(low) AML) in 711 patients entered on seven Eastern Cooperative Oncology Group AML treatment trials (1986-1999). Of those, 198 (28%) qualified as having CD65s(low) AML. Morphologically, CD65s(low) AML was more common in FAB subgroups with minimal differentiation, M0/M1 (P=<0.0001). Early precursor antigens CD34, CD117 and terminal transferase were more frequent in CD65s(low) than CD65s(high) AML (P=<0.0001). Myeloperoxidase was present in fewer CD65s(low) myeloblasts, and the more mature myeloid antigens, CD15 and CD11b, were rarely detected (P=<0.0001). Yet, the two diagnoses did not differ in the distribution of cytogenetic prognostic groups or the occurrence of the multidrug-resistance mediator, P-glycoprotein. CD65s(low) AML patients were significantly older than CD65s(high) cases (P<0.0001). Furthermore, the incidence of CD65s(low) cases increased with age, from 20% in patients under the age of 50 years to 67% in patients older than 80 years (P<0.0001). Overall, complete remission (CR) rate and overall survival were comparable in CD65s(low) and CD65s(high) AML. However, among patients >55 years of age, CD65s(low) AML had a decreased CR rate of 33 vs 44% in CD65s(high) AML (P=0.055). Thus, CD65s(low) AML represents immunophenotypically undifferentiated disease and occurs predominantly in older adults. Although not statistically significant, the observed association between low CD65s expression and decreased CR rate only in patients over the age of 55 is intriguing.

Through the hard work of a large number of investigators, the biology of acute myeloid leukemia (AML) is becoming increasingly well understood, and as a consequence, new therapeutic targets have been identified and new model systems have been developed for testing novel therapies. How these new therapies can be most effectively studied in the clinic and whether they will ultimately improve cure rates are questions of enormous importance. In this article, Dr. Jacob Rowe presents a summary of the current state-of-the-art therapy for adult AML. His contribution emphasizes the fact that AML is not a single disease, but a number of related diseases each distinguished by unique cytogenetic markers which in turn help determine the most appropriate treatment. Dr. Jerald Radich continues on this theme, emphasizing how these cytogenetic abnormalities, as well as other mutations, give rise to abnormal signal transduction and how these abnormal pathways may represent ideal targets for the development of new therapeutics. A third contribution by Dr. Frederick Appelbaum describes how AML might be made the target of immunologic attack. Specifically, strategies using antibody-based or cell-based immunotherapies are described including the use of unmodified antibodies, drug conjugates, radioimmunoconjugates, non-ablative allogeneic transplantation, T cell adoptive immunotherapy and AML vaccines. Finally, Dr. John Dick provides a review of the development of the NOD/SCID mouse model of human AML emphasizing both what it has taught us about the biology of the disease as well as how it can be used to test new therapies. Taken together, these reviews are meant to help us understand more about where we are in the treatment of AML, where we can go and how we might get there.

The associations of cytogenetics with complete remission (CR) rates, overall survival (OS), and outcomes after CR were studied in 609 previously untreated AML patients younger than 56 years old in a clinical trial comparing 3 intensive postremission therapies: intensive chemotherapy, autologous transplantation (ABMT), or allogeneic bone marrow transplantation (alloBMT) from matched related donors. Patients were categorized into favorable, intermediate, unfavorable, and unknown cytogenetic risk groups based on pretreatment karyotypes. CR rates varied significantly (P <.0001) among the 4 groups: favorable, 84% (95% confidence interval [CI], 77%-90%); intermediate, 76% (CI, 71%-81%); unfavorable, 55% (CI, 48%-63%); and unknown, 54% (CI, 33%-74%). There was similar significant heterogeneity of OS (P <.0001), with the estimated relative risk of death from any cause being 1.50 (CI, 1.10-2.05), 3. 33 (CI, 2.43-4.55), and 2.66 (CI, 1.59-4.45) for the intermediate, unfavorable, and unknown risk groups, respectively, compared with the favorable group. In multivariate analyses, the effects of cytogenetic risk status on CR rate and OS could not be explained by other patient or disease characteristics. Among postremission patients, survival from CR varied significantly among favorable, intermediate, and unfavorable groups (P =.0003), with significant evidence of interaction (P =.017) between the effects of treatment and cytogenetic risk status on survival. Patients with favorable cytogenetics did significantly better following ABMT and alloBMT than with chemotherapy alone, whereas patients with unfavorable cytogenetics did better with alloBMT. Cytogenetic risk status is a significant factor in predicting response of AML patients to therapy; however, to tighten treatment correlates within genetically defined AML subsets, a significantly larger leukemia cytogenetic database is warranted.

The prognosis for patients with acute myeloid leukemia in first relapse is generally poor. The ability to induce a second complete remission (CR) with the same chemotherapy used in initial induction therapy is limited. Remission inversion rate, defined as achieving a longer second CR than the first CR in response to standard chemotherapy for relapse, is important in assessing studies of novel chemotherapy or immunologic treatment strategies for patients with relapsed disease. One hundred and twenty-four patients entered on two Eastern Cooperative Oncology Group (ECOG) studies for patients with relapsed AML were analyzed to determine the remission inversion rate. Twenty-two of the 124 patients (18%; 95% confidence interval 12-26%) experienced a longer second CR duration than the first CR duration by at least 2 months. Inversion of CR duration is thus not a rare event. The inversion frequency reported here establishes a baseline upon which future studies in relapsed disease need to be defined.

The overall strategy for the treatment of older adults is summarized in Table 8. Soon after the birth of effective chemotherapy for acute leukemia, the perspective for all patients was summarized as follows: 'With all humility it may be claimed that there are, at least, grounds for hope and encouragement in this recently acquired ability occasionally to halt for a while the formerly unrelenting malignant process known as acute leukemia'. In reviewing the overall survival data for older adults one may feel that we are at a similar juncture in assessing the outcome for this particular population. It is hoped that some of the potential advances may provide greater hope and improved results over the next decade.

A potential mechanism of chemotherapy resistance in acute myeloid leukemia (AML) is the multidrug resistance (MDR-1) gene product P-glycoprotein (P-gp), which is often overexpressed in myeloblasts from refractory or relapsed AML. In a multicenter phase II clinical trial, 37 patients with these poor risk forms of AML were treated with PSC 833 (Valspodar; Novartis Pharmaceutical Corporation, East Hanover, NJ), a potent inhibitor of the MDR-1 efflux pump, plus mitoxantrone, etoposide, and cytarabine (PSC-MEC). Pharmacokinetic (PK) interactions of etoposide and mitoxantrone with PSC were anticipated, measured in comparison with historical controls without PSC, and showed a 57% decrease in etoposide clearance (P =.001) and a 1.8-fold longer beta half-life for mitoxantrone in plasma (P <.05). The doses of mitoxantrone and etoposide were substantially reduced to compensate for these interactions and clinical toxicity and in Cohort II were well tolerated at dose levels of 4 mg/m2 mitoxantrone, 40 mg/m2 etoposide, and 1 g/m2 C daily for 5 days. Overall, postchemotherapy marrow hypoplasia was achieved in 33 patients. Twelve patients (32%) achieved complete remission, four achieved partial remission, and 21 failed therapy. The PK observations correlated with enhanced toxicity. The probability of an infectious early death was 36% (4 of 11) in patients with high PK parameters for either drug versus 5% (1 of 20) in those with lower PK parameters (P =.04). P-gp function was assessed in 19 patients using rhodamine-123 efflux and its inhibition by PSC. The median percentage of blasts expressing P-gp was increased (49%) for leukemic cells with PSC-inhibitable rhodamine efflux compared with 17% in cases lacking PSC-inhibitable efflux (P =.004). PSC-MEC was relatively well tolerated in these patients with poor-risk AML, and had encouraging antileukemic effects. The Eastern Cooperative Oncology Group is currently testing this regimen versus standard MEC chemotherapy in a phase III trial, E2995, in a similar patient population.

Background: One potential mechanism of drug resistance to chemotherapy is the overexpression of multidrug resistance (MDR) genes coding for P-glycoprotein (P-gp), which leads to reduced intracellular retention of chemotherapy. This study tested the efficacy and toxicity of mitoxantrone, etoposide, and intermediate dose cytarabine (MEC) with cyclosporine (CSP) as an MDR modulator in patients with recurrent and refractory acute myeloid leukemia, and also correlated P-gp expression in leukemia cells with response., Methods: Thirty-eight eligible patients who were in first recurrence after < 6 months of complete remission (CR) (11 patients), refractory to initial induction therapy or to one attempt at reinduction after recurrence (18 patients), in second recurrence (4 patients), or in recurrence after either allogeneic or autologous bone marrow transplantation (5 patients) received either MEC alone (13 patients) or MEC-CSP (25 patients). CSP was given as a loading dose of 6 mg/kg for 2 hours intravenously (i.v.) starting 2 hours before the first dose of etoposide, followed by a continuous i.v. infusion of 18 mg/kg/day for 98 hours., Results: Three of the 13 patients (23%) who received MEC achieved CR, as did 6 of the 25 patients (24%) who received MEC-CSP. The median remission duration for all patients who achieved CR was 149 days (range, 26-466 days), 91 days (range, 81-172 days) for the 3 patients who received MEC, and 189.5 days (range, 26-466 days) for the patients treated with MEC-CSP. The median survival for the patients treated with MEC and MEC-CSP was 104 and 72 days, respectively., Conclusions: No significant association was found between P-gp expression and response. No apparent benefit in the CR rate, remission duration, or survival was observed with the addition of CSP to MEC.

Background: In young adults with acute myeloid leukemia, intensive chemotherapy during the initial remission improves the long-term outcome, but the role of bone marrow transplantation is uncertain. We compared high-dose cytarabine with autologous or allogeneic marrow transplantation during the first remission of acute myeloid leukemia., Methods: Previously untreated adolescents and adults 16 to 55 years of age who had acute myeloid leukemia received standard induction chemotherapy. After complete remission had been achieved, idarubicin (two days) and cytarabine (five days) were administered. Patients with histocompatible siblings were offered allogeneic marrow transplantation, whereas the remaining patients were randomly assigned to receive a single course of high-dose cytarabine or transplantation of autologous marrow treated with perfosfamide (4-hydroperoxycyclophosphamide). Oral busulfan and intravenous cyclophosphamide were used as preparative regimens for both allogeneic and autologous marrow transplantation. The end points were survival from the time of complete remission and disease-free survival., Results: In an intention-to-treat analysis, we found no significant differences in disease-free survival among patients receiving high-dose chemotherapy, those undergoing autologous bone marrow transplantation, and those undergoing allogeneic marrow transplantation. The median follow-up was four years. Survival after complete remission was somewhat better after chemotherapy than after autologous marrow transplantation (P=0.05). There was a marginal advantage in terms of overall survival with chemotherapy as compared with allogeneic marrow transplantation (P=0.04)., Conclusions: A postinduction course of high-dose cytarabine can provide equivalent disease-free survival and somewhat better overall survival than autologous marrow transplantation in adults with acute myeloid leukemia.

Clinical data regarding the use of colony-stimulating factors for the treatment of acute myeloid leukemia (AML) are conflicting because of varying study conditions. Interpretation of data is affected by differences in patients' ages, induction regimens, the timing of growth factor administration, the presence of marrow hypoplasia, disease states, differences in the products used, and statistical endpoints. Most trials of granulocyte colony-stimulating factor (GM-CSF) have demonstrated a significant shortening of neutrophil recovery time and a trend toward higher rates of complete remission. Several studies have demonstrated a significant reduction in the rates of morbidity or early mortality with G-CSF or GM-CSF. In vitro data support the concept of enhancing antimicrobial activity with macrophage colony-stimulating factor or GM-CSF. The safety and potential benefit of these cytokines suggest that cytokines should be administered to patients receiving induction therapy for AML who are at high risk for therapy-related morbidity and mortality.

While assessing the prognostic implications of immunophenotyping in 382 patients enrolled in treatment protocols of the Eastern Cooperative Oncology Group (ECOG) for de novo adult acute myeloid leukaemia, we identified 95 patients with a unique antigen profile characterized by high expression of the leucocyte integrin CD11b (CD11b+ AML). High expression of CD11b was defined as > or = 32% positive blasts based on the retrospectively established prognostic cut-off point for this antigen. Although CD11b is normally expressed by mature monocytes, natural killer cells and granulocytes, leukaemic blasts in CD11b+ AML lacked other immunologic monocytic features (e.g. CD14 and CD122, the interleukin-2 receptor beta chain) and demonstrated a high degree of immaturity, as reflected by a high incidence of blasts expressing the stem cell factor receptor, CD117, and few blasts positive for the myeloid differentiation antigen CD15. Furthermore, by FAB criteria, only 41% of CD11b+ AML cases were classified as M4/M5. Patients with CD11b+ AML had a low response rate (54%) when compared with acute monocytic leukaemia (AMOL; 82%, P = 0.006) or AML overall (68%, P = 0.031), independent of age, cytogenetic abnormalities and P-glycoprotein expression. Because of its poor prognosis, recognition of CD11b+ AML is clinically warranted and, given its morphologic and cytogenetic ambiguity, must be based on the unique antigen profile.

Background: The data base of the Eastern Cooperative Oncology Group (ECOG) provides access to data on a large adult patient population drawn from more than 25 major university institutions and hundreds of participating hospitals. Extensive medical files are maintained at the ECOG Coordinating Center and are updated regularly., Methods: Data on 1414 eligible patients with acute myeloid leukemia (AML), treated on 6 ECOG protocols during the period 1976-1994, were reviewed to determine the number of long-term survivors (LTS) and to identify factors that predicted LTS. Disease free survival and factors impacting quality of life were examined as well., Results: Of the 1414 patients, 274 survived for > or = 3 years and were considered LTS. A logistic regression analysis revealed that factors predicting LTS included age < 55 years, female gender, treatment between 1985 and 1990, white blood cell count < 10,000 cells/mm3, and hemoglobin > 10 g/dL. Disease free survival improved with escalating intensity of therapy. Quality-of-life data showed that infections were fairly common. Significant graft-versus-host disease occurred in 6 of 40 patients who received allogeneic bone marrow transplantation and contributed to the deaths of 4 individuals. Information on employment, insurance, social or marital difficulties, and psychosocial issues was more difficult to obtain., Conclusions: Prognosis in AML is a complex interaction involving the cellular origin of the malignant clone, morphology, and evolving therapeutic strategies. The most recent ECOG studies incorporate these variables and should provide additional insights into factors affecting LTS in patients with AML.

The use of colony-stimulating factors (CSFs) in acute myeloid leukemia (AML) remains controversial. Potential uses include shortening the period of neutropenia, inducing leukemic cells into the S-phase of the cell cycle, stem cell protection, inducing differentiation of leukemic cells, interrupting autocrine/paracrine loops, direct inhibition of leukemogenesis, and enhancing antimicrobial function. Data from the nine controlled studies of CSFs that have been reported between 1990 and 1995, with varying patient characteristics and other factors, indicate that growth factors have several uses in AML therapy. The published literature now suggests that the safety of CSFs is no longer a major clinical concern, and significant experience has been gained in reducing the period of neutropenia following induction therapy. Yeast-derived granulocyte-macrophage colony-stimulating factor and granulocyte colony-stimulating factor appear to be effective and probably have an important role in the management of older adult patients with AML and for those patients with a significant risk for therapy-related morbidity and mortality. The use of CSFs as priming agents remains experimental; results of further prospective placebo-controlled studies, with laboratory correlates, are awaited.

Current induction chemotherapy regimens afford a complete remission in 60 to 80% of patients less than 60 years of age who are diagnosed with acute myelogenous leukaemia. Patients who undergo consolidation with high dose Ara-C or with autologous or allogeneic bone marrow transplantation can expect a long-term disease free survival of 30 to 45%. Which mode of consolidation is preferable is still being investigated in randomized studies. Many disease characteristics have been put forward as prognostic variables in treatment outcome and as understanding of the biology of AML has continued to expand, cytogenetic and molecular markers have assumed greater importance in disease characterization, but the ultimate role that these play in prognosis remains incompletely defined. Once AML has relapsed, bone marrow transplantation may result in prolonged disease free survival as compared to use of salvage chemotherapy regimens. Because the long-term survival of all patients diagnosed with AML is only in the order of 10 to 20%, new treatment approaches to this disease are required. Current clinical and research efforts have focused on modulation of the immune system, modulation of drug resistance phenotypes, and understanding of the response of leukaemic cells to haematopoietic growth factors.

The treatment of adult patients greater than 55 to 70 years of age with acute myelogenous leukemia (AML) is associated with a treatment-related mortality of approximately 25%. This prospective, double-blind randomized study was designed to see if the use of granulocyte-macrophage colony stimulating factor (GM-CSF; yeast-derived) could shorten the period of neutropenia and to determine any effect this would have on therapy-related morbidity and mortality. A total of 124 patients entered this study. Induction consisted of standard daunorubicin and cytarabine. A day-10 bone marrow was examined; if this was aplastic without leukemia, patients received blinded placebo or GM-CSF from day 11 until neutrophil recovery. Patients who entered complete remission received the identical study medication (blinded GM-CSF or placebo) in consolidation that they had received during induction. The overall complete remission rate was 52%; 60% for the GM-CSF arm and 44% for the placebo arm (P = .08). Median times to neutrophil recovery were significantly shortened on the GM-CSF arm. The overall treatment-related toxicity from start of GM-CSF/placebo was reduced on the GM-CSF arm (P = .049). Similarly, the infectious toxicity was significantly reduced on the GM-CSF arm (P = .015). The median survival for all patients was 10.6 months in the GM-CSF group and 4.8 months in the placebo arm (P = .048). It appears that GM-CSF is safe and efficacious for adult patients greater than 55 to 70 years of age with AML; its major impact is in reducing the duration of neutropenia and therapy-related mortality and morbidity. This may result in a better response rate.

It is now known that syngeneic transplantation, T lymphocyte depletion and absence of graft-versus-host disease all increase the risk of relapse following allogeneic transplantation for the myeloid leukemias, both acute and chronic. Leukemia-specific immune responses appear to play a major role in the therapy of the myeloid leukemias. In recent years attempts have been made to better characterize and effectively utilize these antileukemic immune responses, concentrating on clinical states of minimal residual disease. This review will discuss the role of such immunotherapy following autologous bone marrow transplantation for myeloid leukemias, and will focus on recent experience and ongoing clinical trials using the novel immunomodulator Linomide.

Leukapheresis was used as the sole modality of treatment of a patient with chronic myelogenous leukemia (CML) during her pregnancy. The specific requirements for safe leukapheresis during pregnancy are discussed, and the literature describing the management of CML during pregnancy is reviewed. Leukapheresis may be the treatment of choice in selected pregnancy patients with CML since it avoids the potential teratogenic effects of chemotherapy or radiation therapy.

Ten patients under 20 yr of age with the usual (adult) type of chronic myelogenous leukemia (CML) were seen at the University of Rochester Medical Center from 1970 to 1982. The mean white cell count in these 10 patients at presentation was 360,000/microliter, as compared to a mean of 137,000/microliter in 80 CML patients over 20 yr of age seen during the same time interval (p less than 0.02). Analyses of all 90 cases revealed a significant decrease in the average leukocyte count at presentation with increasing age. The childhood cases also had a significantly higher proportion of blood blasts, promyelocytes, and myelocytes than did the adult subjects (p less than 0.01). Signs of leukostasis were present in 12% of adult cases as compared to 60% of the 10 childhood cases, and in these 6 subjects, the mean white cell count was 510,000/microliter. In these 6 patients, leukapheresis and/or chemical therapy was initiated rapidly, and this was followed by complete resolution of the clinical signs of leukostasis. A review of the literature from 1960 to 1982 identified 61 childhood cases that were reported with the usual type of CML. In this group, the frequency of hyperleukocytosis and the distribution of white cell counts corresponded very closely to the 10 cases studied at the University of Rochester. Thus, the usual type of CML presenting in childhood differs from that of adults in that hyperleukocytosis, blood granulocyte immaturity, and leukostatic central nervous system, retinal, and respiratory signs are significantly more common and extreme and merit rapid cytoreductive treatment.